Along with the rapid development of urbanization, the energy problem is increasingly prominent. Based on CES production function and growth function of urbanization, this paper put forward the model of Growth Drag of China's Urbanization Caused by energy, and empirical analysis with the data of China was done. The results showed that the growth drag of energy during urbanization process in China is 0.2692,in other words, because of the restriction of energy, urbanization process declines 0.2692.From the results, the Growth Drag of China's Urbanization Caused by energy is very high. Ensure that energy security supply has become one of the important tasks for our country at present.